This invention relates to surface cleaning tools and more particularly to a surface cleaning tool or a wall brush for a vertical face in an earth formation.
Wall tools or wall brushes may be used for dislodging loose material such as rock from a wall face such as a quarry face or other rock face so that men and equipment can work safely on a floor below the face. It is important for safety reasons to remove loose rock or other loose matter on a wall face below which people will be working. Common sense dictates that workers should be protected from falling objects lest they be injured by loose pieces of rock or other material falling on them. Moreover, the Mine Safety and Health Administration (MSHA) has issued regulations relating to pit wall safety, see 30 CFR 56.3-1, 56.3-4 and 56.3-6.
A number of tools have been tried for dislodging loose material from a wall face including a chain attached to a winch on a front end loader and a ball and chain connected to a bull-dozer moving in a parallel direction to the wall face, thereby slamming the ball on the chain against the rock face. None of these tools have proven to be particularly successful and effective in removing loose matter from the wall face. Some of the tools did not dislodge all the loose material on the wall face and others did not have adequate flexibility and hence had an undesirable tendency to get hung up on ledges or in cracks in the wall face.
A number of different tools have been used for scraping or mining a vertical face. For example, U.S. Pat. No. 3,904,244 issued to Haspert discloses a broach which is brought into contact with a working face of a trench. The broach is suspended from a drilling rig by means of a drill stem. The broach has a cutting surface which is provided with a plurality of cutting teeth. The interior of the broach may be filled with lead or other suitable material to provide the broach with sufficient weight to force it against the working face of the trench. However, such a tool is undesirably heavy and tends to dig up the surface rather than dislodging loose material on the surface. Besides that, such a structure is not flexible enough to minimize the problem of hanging on ledges or in cracks.
U.S. Pat. No. 3,802,741 issued to Marceau discloses a scraping device for loosening damaged fire bricks in a crucible of an electric furnace. The scraping device has a beam with a scraping bit disposed on each end face thereof. As the beam is lowered on two cables into the crucible, the scraping bits, which are hingedly connected to the beam, are in an upright, nonworking position since the beam alone has a length approximately equal to the diameter of the fire bricks. The beam, including the scraping bits, has a length approximately equal to the diameter of the shell of the crucible so that when the beam reaches a working position, the bits fall down into the horizontal scraping position. The beam is then raised and lowered repeatedly to cause the bits on each end of the beam to bit into the damaged brickwork to loosen and break it up. However, such a tool has scraping bits disposed only on end faces of a beam such that the beam would have to be presented on end with respect to a wall face in order to dislodge loose material from it.
U.S. Pat. No. 3,937,162 issued to Fukutani discloses a hardened slurry demolishing device for a hold of an iron-ore carrier. A pair of telescopic cylinders suspend a horizontal arm from a traveling platform. The arm is provided at each end with a powered reciprocating breaker which is used to demolish the hardened slurry. However, such a tool is not well suited for scraping wall faces, is not flexibly suspended and requires powered scraping bits.
Still other arrangements for scraping a vertical or a horizontal surface are disclosed in U.S. Pat. No. 2,315,069 (McKeen et al), No. 2,315,252 (Fraser), No. 4,011,618 (Martin et al), No. 4,065,184 (Tipper), but each of these has been found to possess substantial practical disadvantages.
It is therefore an object of this invention to provide a wall tool or wall brush which dislodges loose material from the wall face efficiently, simply and in an economical manner.
It is another object to provide a wall tool which is flexibly suspended to minimize the problem of hanging on ledges or in cracks.
It is still another object of the present invention to provide an inexpensive wall tool or wall brush which has no moving parts.
It is yet another object to provide a wall tool or wall brush which has a plurality of prongs or cleaning teeth disposed on a longitudinal face of a beam which is wide enough and heavy enough to keep the prongs pressed against the wall face which is to be cleaned or brushed.
It is a still yet a further object to reciprocate the wall brush by a cable so that a reciprocating mechanism, for example a crane which lowers and raises the brush, can work far enough behind the wall face so that there is no danger of the weight of the crane causing the top of the wall face to collapse.
These and other objects, as well as the means for achieving them, will become more fully apparent from the specification below.
A wall brush for dislodging loose matter from a wall such as an excavation face, according to the present invention, comprises at least one X-shaped scraper element which brushes against the excavation face and dislodges loose matter therefrom. At least one housing such as a beam is provided to house the scraper element such that end portions of the scraper element project outwardly from flange portions of the beam. A suspension means, preferably an anchor chain, flexibly suspends the beam. The wall brush, which is heavy enough to keep the scraper element pressed against the wall face, is reciprocated, preferably by a crane, on a section of the wall face until it is cleared of loose matter.